Because of the increased sensitivity that the EVLA will
provide, detailed, full-polarization models of the VLA beam
will be necessary in order to do high-fidelity,
noise-limited observations of all four Stokes parameters. We
incorporate into AIPS++ full-polarization model corrections
of the VLA beam patterns. These model corrections are
generated from the antenna simulation program Grasp8.

We then apply these corrections to observations of 3C286 at
two pointings: on axis and at the half-power point. Although
parallel hands (Stokes~I, V) model well, we find that the
the cross-handed data (Stokes~Q, U) are not stable enough
on-axis to allow us sufficient confidence in our off-axis
results. Nevertheless, we compare the observations with our
predictions.

The author(s) of this abstract have provided an email address
for comments about the abstract:
clearf@fas.harvard.edu